60 lines
1.2 KiB
Markdown
60 lines
1.2 KiB
Markdown
# WeakMap
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A WeakMap object is a collection of key/value pairs in which keys must be
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objects. References to key objects in a WeakMap are held weakly, meaning
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they do not prevent garbage collection if there are no other references
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to the object. WeakMap keys are not iterable.
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### set(key, value) <sub>function</sub>
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Set the value for the specified key in the WeakMap. The key must be an object.
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**key**: The object key.
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**value**: The value associated with the key.
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**Returns**: The WeakMap object (for chaining).
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### get(key) <sub>function</sub>
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Return the value associated with 'key' in the WeakMap, or undefined if
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no such key exists. The key must be an object.
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**key**: The object key.
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**Returns**: The value associated with the key, or undefined if not present.
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### has(key) <sub>function</sub>
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Return a boolean indicating whether an element with the specified key
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exists in the WeakMap. The key must be an object.
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**key**: The object key to check.
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**Returns**: True if the key is found, otherwise false.
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### delete(key) <sub>function</sub>
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Remove the specified key and its associated value from the WeakMap,
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if it exists.
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**key**: The object key to remove.
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**Returns**: True if an element was removed, otherwise false.
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